Polymer Library

Thermoplastic Elastomers - May 2017

This month we're looking at Thermoplastic Elastomers

Thermoplastic elastomers (TPEs) were first introduced into the automotive market in the 1960s, and since that time have become a major class of elastomeric materials suitable for use in motor vehicles worldwide. According to a Market Report by Smithers Rapra, automotive and other transportation applications will continue to dominate the end-use market, increasing their market share to 44% by 2020. Rising stars are medical and hygiene applications, as well as those for wire and cable showing the highest CAGRs and jointly occupying about 13% market share in 2015. New cutting-edge technologies are on the horizon, with continuous emphasis on the growth of biomass-sourced TPEs and a possible future for TPE-based smart rubbers.

Why not read some of the latest literature in this area? We've selected some abstracts recently added to the Polymer Library - the world's largest database dedicated to polymer literature.

Abstracts

These abstracts were highlighted in the May Newsletter and found in the Polymer Library.

Click on the 7-digit accession numbers to find out about ordering a copyright-cleared full text copy of the items shown.

1244553 - Thermoplastic elastomers: materials for heart assist devices (OPEN ACCESS - FREE ACCESS TO FULL TEXT)
Heart assisting devices have become a standard element in clinical practice and provide support for the traditional methods of treating heart disease. Regardless of the construction of VAD (ventricular assist devices), there are crucial requirements that have to be met by the construction materials: high purity, desired physical, chemical and mechanical properties, easy fabrication and high stability and susceptibility to sterilisation. They must not cause thrombosis, destroy cellular elements, alter plasma protein, destroy enzymes, deplete electrolytes, cause immune response and cancer, and must not produce toxic and allergic reactions, when they are applied in direct contact with biological tissues and fluids. This paper provides an overview of the polymeric materials as construction materials for cardiovascular support systems, focusing on the group of thermoplastic elastomers, mainly polyurethane and polyester based ones. It also highlights the advantages and disadvantages of currently used materials and the progress in the design of new materials with potential application in the biomedical field. 41 Refs.
Polymers in Medicine, 46, No.1, Jan.-June 2016, p.79-87, ISSN: 0370-0747
Piegat A; El Fray M

1245344 - Autonomic healing of thermoplastic elastomer composed of triblock copolymer
In this paper, we demonstrated that commercially available triblock copolymers such as polystyrene-b-polybutadiene-b-polystyrene (SBS) and polystyrene-b-polyisoprene-b-polystyrene (SIS), used as thermoplastic elastomers, exhibit autonomic self-healing behaviour at room temperature without any chemical reaction even after cutting into two separate pieces. The healing efficiency is improved by immediate recombination after cutting, and is attributed to the destruction of the microstructure, i.e., polystyrene domains, leading to marked molecular mobility. Furthermore, quenched samples with obscure phase-separation exhibit good healing behaviour. Finally, SBS has better healing efficiency than SIS because the solubility parameter of polybutadiene is closer to that of polystyrene than that of polyisoprene; to some extent, the solubility parameter is responsible for enhanced molecular motion owing to the mutual dissolution of both components. 26 Refs.
Journal of Materials Science, 52, No.2, Jan. 2017, p.1214-1220, ISSN: 0022-2461, DOI:10.1007/s10853-016-0419-1
Ritsuko Watanabe; Takumi Sako; Suphat Korkiatithaweechai; Masayuki Yamaguchi

1247192 - Precision synthesis of sustainable thermoplastic elastomers from lysine-derived monomers
Novel renewable thermoplastic elastomers were synthesised by sequential polymerisation of lysine- and itaconic acid-derived monomers. Ring-opening polymerisation of lysine-based O-carboxyanhydride monomer using diethylene glycol as an initiator gave well-defined (alpha),(omega)-dihydroxy functionalised lysine-derived polyesters. The Mn of these polyesters increased with the monomer conversion while retaining relatively narrow molecular weight distributions. Based on the successful controlled polymerisation and esterification of (alpha),(omega)-dihydroxy with 2-bromoisobutyryl bromide, the resultant Br-PL-Br macroinitiator was used for the atom transfer radical polymerisation of N-phenylitaconimide (PhII). Three poly(N-phenylitaconimide)-b-polyester-b-poly(N-phenylitaconimide) triblock copolymers were prepared containing 12 - 25 mol% PPhII, as determined by ^1H NMR spectroscopy. The properties of the obtained triblock copolymer are evaluated as high-performance and renewable thermoplastic elastomer materials. (50 ref)
Journal of Polymer Science Part A: Polymer Chemistry, 55, No.2, 2017, p.349-355, ISSN: 0887-624X, DOI: 10.1002/pola.28394
Shanshan Liu; Xiaojie Zhang; Maosheng Li; Xiuyan Ren; Youhua Tao

1247673 - High-performance TPE provides multiple processing advantages over other TPEs and EPDM in moulded automotive interior parts (OPEN ACCESS - FREE ACCESS TO FULL TEXT)
A new styrene block copolymer thermoplastic elastomer for passenger car interior parts such as cable ducts and grommets has recently been introduced by Teknor Apex Co., it is announced here. New "Sarlink ML-2355B TPE" is said to exhibits improved injection mouldability compared with other elastomers, while providing competitive physical properties and also meeting stringent OEM requirements. This detailed press release offers full information about the advantageous properties of the new elastomer.
Teknor Apex, 1 Nov. 2016

1249647 - Preparation, morphology and superior performances of biobased thermoplastic elastomer by in situ dynamical vulcanization for 3D-printed materials
3D-printing of polymers provides the opportunity to fabricate materials into customised sizes and shapes. The present study describes fully renewable thermoplastic vulcanisates (TPVs) consisting of synthesised biobased elastomer (PLBSI) and poly (lactic acid) (PLA) by in situ dynamic vulcanisation for 3D-printed materials. The morphology study implied in situ dynamic vulcanisation and phase inversion occurs and leads the PLBSI elastomer dispersed as microparticles in PLA matrix. Then, the morphological evolution mechanism was proposed and indicated the dispersed PLBSI elastomer microparticles are actually agglomerates of elastomer nanoparticles. The PLBSI/PLA TPVs perform good processability and reprocessability by rheological and recyclability tests. Besides, good in vitro degradability and cytotoxicity suggests PLBSI/PLA TPVs are promising sustainable biomaterials. The superior strength and elasticity confirmed by the tensile tests of 3D-printed samples, and firm microstructure and the reliable printed accuracy of 3D-printed samples investigated by SEM implied the PLBSI/PLA TPVs were ideal 3D-printing materials. (39 ref)
Polymer, 108, 13 Jan. 2017, p.11-20, ISSN: 0032-3861, DOI: 10.1016/j.polymer.2016.11.045
Xiaoran Hu; Hailan Kang; Yan Li; Yiting Geng; Runguo Wang; Liqun Zhang

1250160 - Antifriction aminopropyltriethoxysilane films on thermoplastic elastomer substrates using an APPJ system
The study of friction coefficients has long been of great importance in the automotive industry where some areas of the vehicle are subject to slippage. One example is the space between the window channels and the glass. The polymeric materials that are used in these areas, like thermoplastic elastomers (TPE), involve a high degree of friction. So, in order to decrease the friction coefficient of the TPE, companies are using such techniques as flocking. However their high energy consumption, irregular distribution of fibres and poor adhesion are drawbacks. In order to overcome these drawbacks, this work attempts to obtain a SiOx-based thin film over a TPE substrate using aminopropyltriethoxysilane (APTES) with similar or lower friction coefficients and the same durability. Since TPE is heat-sensitive, an atmospheric-pressure plasma jet system (APPJ) with a dielectric barrier discharge (DBD) was used in this study. The influence of the plasma power and number of passes was characterised by Profilometry, Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM), Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) Spectroscopy, X-Ray Photoelectron Spectroscopy (XPS), Water Contact Angle (WCA) measurements and friction coefficient. The average surface temperature of the samples and the coating thickness seem to be the key variables in determining the friction behaviour. Successful samples (those that have a lower friction coefficient than those of the current industrial solutions - flocked seals and polyamide tap) were coated at an average surface temperature of <92 deg. C and thicknesses of the coatings were >1000 nm. Sample coated in six passes and the lowest power (350 W) proved to have the best friction performance. This sample has a friction coefficient that is 46% lower than that of the flocked seals. The results of this research permit one to conclude that a promising antifriction technology using APPJ with a DBD could be an alternative to the current industrial solutions. (46 ref)
Surface and Coatings Technology, 310, 25 Jan. 2017, p.239-250, ISSN: 0257-8972, DOI: 10.1016/j.surfcoat.2016.12.079
Sainz-Garcia E; Alba-Elias F; Mugica-Vidal R; Gonzalez-Marcos A

1251179 - Meet the polymer superheroes
A look is taken at high-performance polymers, such as PEEK and thermoplastic elastomers, whose properties, such as strength, heat resistance and chemical resistance, exceed those of conventional polymers, and at the factors to be considered when selecting such a material for medical applications. 6 refs
Medical Plastics News, no. 34, Jan-Feb. 2017, p.38-39, ISSN: 2047-4741
Padbury R

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